There might be some better way to track multiple components that are added are combined than what I'm going to suggest.
In this case multiple DS lots are added to formulate a DP lot. Often we know more information about the DS Lot, like maybe (hopefully) it's "test value", and how much was added to the DP lot.
What I might want to visualize is how much of each DS lot went into each DP lot. I might also want to model the expected vs. actual "test values" for the DP lots. (sometimes the DS and DP lots are tested at times very far apart, and test method performance drift results in DP lots with much higher or lower "test values" than expected.
For simplicity, I would likely keep a separate table for each of the DS and DP lots, and this intermediate table for keeping track of what components go into each DP. When I need to, then I can use virtual joins to combine the data.
This is a hard problem to work with. If anyone else has a better data structure, I'd certainly like to hear about it.
JMP Systems Engineer, Health and Life Sciences (Pharma)